Three dimensional textile carbon fiber reinforced silicon carbide (3D textile C/SiC)
composites with pyrolytic carbon interfacial layer were fabricated by chemical vapor infiltration.
The microstructure and mechanical property of 3D textile C/SiC composites were investigated. A
thin pyrolysis carbon layer (0.2 ± μm) was firstly deposited on the surface of carbon fiber as the
interfacial layer with C3H6 at 850°C and 0.1 MPa. Methyltrichlorosilane (CH3SiCl3 or MTS) was
used for the deposition of the silicon carbide matrix. The conditions used for SiC deposition were
1100°C, a hydrogen to MTS ratio of 10 and a pressure of 0.1 MPa. The density of the composites
was 2.1 g cm-3. The flexural strength of the 3D textile C/SiC composites was 438 MPa. The 3D
textile C/SiC composites with pyrolytic carbon interfacial layer exhibit good mechanical properties
and a typical failure behavior involving fibers pull-out and brittle fracture of sub-bundle. The real
part (ε′) and imaginary part (ε″) of the complex permittivity of the 3D-C/SiC composites are
51.53-52.44 and 41.18-42.08 respectively in the frequency range from 8.2 to 12.4 GHz. The
3D-C/SiC composites would be a good candidate for microwave absorber.